As a general rule, ionizing radiation is most damaging to

Options

A. Mature, stable cells
B. Actively dividing cells
C. Highly specialized cells
D. Cells in which food is stored

Answer

**Step-by-Step Solution:**

1. **Understanding Ionizing Radiation**: Ionizing radiation is a type of radiation that has enough energy to knock electrons out of atoms, which can lead to the formation of ions. This process can damage the molecular structure of cells, particularly affecting DNA.

2. **Identifying Cell Types**: The question presents four types of cells:
- Mature or stable cells
- Actively dividing cells
- Highly specialized cells
- Cells in which food is stored

3. **Analyzing Sensitivity to Radiation**:
- **Mature or Stable Cells**: These cells are typically not dividing and are more resistant to radiation damage.
- **Actively Dividing Cells**: These cells are in a constant state of division and are more susceptible to damage from ionizing radiation because their DNA is actively replicating.
- **Highly Specialized Cells**: These cells have specific functions and may not divide frequently, making them less sensitive to radiation.
- **Cells in Which Food is Stored**: These cells are usually not actively dividing and are also less sensitive to radiation.

4. **Conclusion**: Based on the analysis, actively dividing cells are the most sensitive to ionizing radiation due to their rapid division and the presence of DNA that is vulnerable to damage. Therefore, the correct answer is that ionizing radiation is most damaging to **actively dividing cells**.

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